no-administration heap?

[Keith Holdaway]

Just discovered that I was running JDK 6.0 locally and JDK 5.0 remotely -

thanks - it works now.

keith

Keith R Holdaway
Java Development Technologies

SAS The Power to Know

Carpe Diem


-----Original Message-----
From: hotspot-gc-dev-bounces at openjdk.java.net [mailto:hotspot-gc-dev-bounces at openjdk.java.net] On Behalf Of Keith Holdaway
Sent: Thursday, February 28, 2008 5:45 PM
To: hotspot-gc-dev at openjdk.java.net
Subject: RE: no-administration heap?

Gentlemen,

I am trying to remotely connect to a running VM with visualgc.

Here is the DOS command from my shell on the box containing visualgc 3.0_b07

C:\Documents and Settings\kehold>visualgc 4664 at AMDSRV4.na.sas.com 1000
Exception in thread "main" java.lang.NullPointerException
        at com.sun.jvmstat.tools.visualgc.MonitoredVmModel.getOsFrequency(Monito
redVmModel.java:485)
        at com.sun.jvmstat.tools.visualgc.GCSample.initStaticCounters(GCSample.j
ava:104)
        at com.sun.jvmstat.tools.visualgc.GCSample.<init>(GCSample.java:129)
        at com.sun.jvmstat.tools.visualgc.VisualGC.main(VisualGC.java:128)

I have kicked off a VM with jps - LVMID 4664 on the remote box AMDSRV4.

I can run visualgc locally - I have run rmiregistry and established a jstatd.all.policy file on the remote box:

grant codebase "file:${java.home}/../lib/tools.jar" {
   permission java.security.AllPermission;
};

Any ideas? The local box is 32 bit Hotspot; the remote box a 64 bit running Hotspot.

Keith R Holdaway
Java Development Technologies

SAS The Power to Know

Carpe Diem


-----Original Message-----
From: hotspot-gc-dev-bounces at openjdk.java.net [mailto:hotspot-gc-dev-bounces at openjdk.java.net] On Behalf Of Colin Walters
Sent: Thursday, February 28, 2008 4:59 PM
To: Florian Weimer
Cc: hotspot-gc-dev at openjdk.java.net
Subject: Re: no-administration heap?

On Thu, Feb 28, 2008 at 4:20 PM, Florian Weimer <fw at deneb.enyo.de> wrote:
>
>  At least on Linux, the problem is that there is no documented API to
>  reserve address space (so that no other mappings end up there) without
>  actually allocating backing store.  MAP_NORESERVE does not work as
>  documented.

Ah, I see.  So this problem is essentially blocked on the lack of a
sufficient/documented Linux kernel interface?
Do other operating systems (Windows, Solaris) provide a good enough
interface for OpenJDK?

I'm assuming changing the collector to not require a continuous
address space would be too invasive?